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Smart robots and smart services using robots are promising research fields in academia and industry. However, those smart services are based on basic motions of the robot, such as grabbing objects, and moving them to a designated place. In this paper, we propose a way to produce new motions without programming, from existing motions, through a motion composition method. Our motion composition method utilizes an Action Petri net, which is a variance of a Petri net, with both interpolation and composition operations on a transition. In the Action Petri net, a place is a posture or a moving action of a robot, and it is represented as a diagonal matrix with the robot's joint motor values. Robot motions can be generated from one posture to another posture, and from composing different postures and moving actions. All operations performed to generate new motions are carried out as matrix manipulation operations. Our approach provides a formal method to generate new motions from existing motions, and a practical method to create new motions in low level motion control, without programming.
The demand for materials of superior properties is increasing day by day. Due to this materials scientist are developing new materials to meet the demand of growing need of materials. The material scientist for the development of metal matrix composite has been given much attention, which are continuously replacing traditional materials. There are several fabrication techniques for the production of MMC. Among the fabrication processes of MMCs of recent development, powder metallurgy is one of the most widely used fabrication techniques. Powder Metallurgy (P/M) offers designers and users a versatile and efficient method of producing components. The process is versatile because it can be used for simple and complex shapes, and a full range of chemical, physical and mechanical properties is possible to obtain. P/M is efficient because it produces moderate to high-volume net or near-net shapes, with very little raw material loss. In general, the process has very good potential to improve performance through uniform properties, fine grain structures, and chemical homogeneity. During the process, the matrix material powders and the reinforcement particles are blended to produce a homogeneous distribution and fed into a mould of desired shape, hot press to a desired level of compaction and final consolidation by extrusion, forging, rolling or some other hot working method. The powder metallurgy attracted attention of the parts manufacturer during the last decades based on progress in materials, process and equipment. The conventional powder metallurgy process consists of three main-steps: powder mixing, compacting (sintering) and extrusion. To carry out the processing of MMC through powder metallurgy, development of powder metallurgy set up is essential. Powder metallurgy set up consists of several main parts such as die, mould, in which the powder is contained, punches, which are used to apply compacting pressure and heater for hot compaction as well as hot extrusion of MMCs. The main aim of the article is to discuss model design, process planning and fabrication of powder metallurgy set up as well as heating system for hot compacting /extrusion (direct and indirect).